Leakage-prevention arrangement for fuel-tanks



. E.THOMSON. LEAKAGE PREVENTION ARRANGEMENT FOR FUEL TANKS.

APPLICATION H !.ED SEPT. a, 1919. 1,365,567.

Patented Jan. 11

lnventlcgm' Elihu Thomson,

HIS Attorney.

nrrun STATES- P EEN-r otter.

Enrnn rnomson or LYNN, nassaonusn'rrs, ASSIGNOR 'ro GENERAL ELECTRICCOMPANY, A CORPORATION on new roan.

LEAKAGE-PREVENTION ARRANGEMENT FOR FUEL-TANKS.

naeaaev.

Specification of Letters Iatenc.

Patented Jan. 11, 1921.

Application filed September 8, 1-919. Serial No. 322,471.

T all whom it may concern:

' Be it known that I ELIHU THOMSON, a

citizen of the United States, residing at L nn, in the county of Essex,State of assachusetts, have invented certain new and useful Improvementsin Leakage-Prevention Arrangements for Fuel-Tanks, of

' which the following is a specification.

The present invention relates to fuel tanks such as gasolene tanks usedto supply 'fuel to engines, and has for its object to pro-- vide animproved structure and arrangement whereby should a hole he made in thefuel tank nevertheless it will not leak.

One particular application of my invention is in connectiom with fueltanks for the engines of aeroplanes where a leak in the tank, caused,for example, by a bullet, may be a very serious matter. Anotherapplication of my invention is in connection cable.

For a considerationof what I believe to be novel in my invention,attention is directed to the accompanying specification and the claimsappended thereto.

In the drawing Figure l is a diagrammatic view partly in section of anarrangement embodying my invention; Fig. 2 is an end view on a smallerscale of the fuel tank shown in Fig. 1 and Fig. 3 is a seetional view ofa modification.

Referring to the drawing 5 indicates an internal combustion engineprovided with a suitable carbureter 6 to which fuel is supplied by aconduit 7 The discharge outlet 8 of the carbureter is connected to theintake manifold 9 of the engine and the air inlet 10 of the carbureteris connected to an air conduit 11 through which air is fed to thecarbureter. The engine and carbureter arrangement shown may be taken astypical of any such apparatus. The operation is well understood andneeds no description.

Now according to my invention, I provide a fuel tank for the engine anda suitable pumping means for pumping fuel fromthe lower portion orbottom of said tank and I feeding it to the carbureter. I also providein connection with the fuel tank a second pumping means, which may be inthe form of a suction fan, and which is connected to the top of the fueltank above the level of the fuel therein, so as to maintain a partialvacuum therein. With this arrangement, in case a holeis made in the tankproducing a leak, then instead of fuel leaking out of the tank throughthe hole, air will be sucked into it through the hole and discharged bythe pump means which creates the partial vacuum in the tank. By

this means leakage of fuel through the hole will be prevented. Tominimize the leakage which may occur due to a hole in the fuel tank, Iprovide the tank with an inner acket or lining of a felted mass which isso strongly woven that it will partially close a perforation madethrough it. Or instead of a felted mass I may use any other materiailwhich will accomplish the desired resu t.

I The air pumped from the fuel tank by the vacuum producing pump meanswill always contain somefuel vapor and in case of-a hole in the tank,will be highly carbureted. To avoid inflammable vapors floating around,and also to utilize them, I connect thedischarge side of the vacuumproducing pump means to the air inlet of the carburetor so such vaporswill be fed to the engine. I also provide suitable means for controllingthe vacuum producing pump means and for admitting air to dilute themixture discharged by' such pump means when too highly carbureted.

Where the apparatus always remains in vertical position, the two pumpmeans may be connected directly with the bottom and the top of the fueltank respectively. In cases, however, where the angle may vary, such as,for example, aeroplanes and ships, I preferably arrange the apparatus sothat the two pump means always remain connected with the bottom of thetank and with the space above the fuel therein,irrespec- Eve of theangle which the fuel tank may In Figs. 1 and 2, I have illustrated thelatter arrangement.

12 indicates a fuel pump which may be of any suitable type and drivenand controlled in any suitable manner. In the present instance, areciprocating pump is illustrated driven by an eccentric 13 on a shaft14. The suction and discharge valves for pump 12 are indicated at 12 and12". The discharge side of pump 12 is connected to supply conduit 7 andthe suction side is connected to a suction pipe, 15. The fuel tank,indicated at 16, is lined with a felted material 17 as referred toabove, and is made in the form of a flat drum with disk like ends. Fueltank 16 is rigidlysupported with respect to the engine and at the centerof one end is provided with a tube 18 which projects into the tank abouthalf way and is rigidly fixed to the tank. The free end of pipe 15extends through the center of the tube 18, being supported therein by aspider-19, and is closed by a plug 20. Pivotally mounted on the ends oftube 18 and pipe 15 is an air conduit 21, the outer end-of whichterminates near the top of the tank and above the level of the fueltherein. The inner end of conduit 21 communicates with tube 18. It isdesirable that conduit 21 turn freely on tube 18 and pipe 15.Accordingly, between conduit 21 and tube 18 is a suitable ball bearing22, over which is placed a flap of soft material 23, such as leather orthe like. This covers the joint and prevents fuel from leaking throughthe joint into the air conduit. The end of pipe 15 is located in abearing sleeve 24 carried by conduit 21. Depending from'conduit 21 is afuel pipe 25, the outer end of which terminates adjacent the bottom oftank 16 and carries a weight 26, the purpose of which is to keep conduit21 and fuel pipe 25 always in vertical position, as shown in Fig. 1. Theinner end of pipe 25 projects through conduit 21 and communicates withthe interior of a housing 27, which is pivotally mounted on pipe 15inside air conduit 21. I11 pipe 15 are one ormore holes 28 which connectthe interior of pipe 15 with housing 27. It will thus be seen that airconduit 21 and fuel pipe 25 form an integral structure which can turnfreely on the ends of tube 18 and pipe '15 and which is alwaysmaintained in a vertical position due to weight 26.

Connected to tube 18 outside tank 16 is an air pipe 29, which leads tothe suction side of a suction pump 30. Pump 30 is shown as being acentrifugal suction fan and its discharge conduit 31 is connected to airconduit 11.' Pump 30 may be driven in any suitable manner. In dischargeconduit 31 is a controlling valve 32'adapted to be 0pside of the pumpwill be increased thereby diminishing the quantity of air pumped. Inother words, closing valve 32 more or less increases the resistance tothe flow of air through pipe 31, thereby diminishing the amount of airhandled-by the pump. Connected to conduit 31 is an auxillary air inletconduit 34, in which is a valve 35 adapted to be controlled by rod 36. i1

In operation, fuel pump 12 pumps fuel from tank 16 through pipes 25 and15 and delivers it through pipe 7 to carbureter 6. At the same time airpump 30 maintains a partial vacuum in tank 16, the air and vapors pumpedout being drawn out through conduit 21, tube 18 and conduit 29 anddelivered through conduit 31 to air conduit 11, and thence to theengine. air valve 35 will normally be closed and valve 32 will be set togive the desired regulation to pump 30. If, now, fuel tank 16 shouldhave a hole made through it, for example by a bullet passing through itas indicated in Fig. 3 at A, then instead of fuel leaking out, air willbe sucked in through the hole or holes and delivered by pump 30 to theair inlet of the carbureter. If this air is too highly carbureted, valve35 may be opened to dilute the mixture to the desired extent.

The arrangement shown in Fig. 1 is one Well adapted for use inconnection with an aeroplane and it will be clear that due to airconduit 21 and fuel pipe 25 being pivoted on the ends of tube 18 and pie 15, even should the aeroplane fly up-sideown, nevertheless, airconduit 21 and fuel pipe 25 will remain vertical. Air conduit 21 willthus remain connected to the space above the fuel in tank 16 and fuelpipe 25 will remain in communication with the bottom thereof.

In Fig. 3 I have shown an arrangement which may be used where the angleof the tank is not subject to change. In this case air conduit 29*,corresponding to air conduit 29 of Fig. 1, is connected directly to thetop of fuel tank- 16" and fuel pipe 15f, correspondin to fuel pipe 15 atFig. 1, is connected rectly to the bottom thereof. Otherwise, thearrangement may be the same as that of Fig. 1. I

In accordance with the provisions of the patent statutes, I havedescribed the principle of operation of my invention, together with theapparatus which I now consider to represent the best embodiment thereof,but I desire to have it understood that the apparatus shown is onlyillustrative and that the invention may be carried out by other meansWhat I claim as new and desire to secure by Letters Patent of the UnitedStates, is: erated by rod 33. Valve 32 is used to regulate pump 30. Byclosing it to a greater or lesser extent the pressure on the discharge,

1. The combination with an engine a fuel tank, and means for supplyingfuel from the tank to the engine, of pump means for suckin air from thetop of said tank to continuous y maintain a partial vacuum therein and avalve means on the delivery side of said pump means for regulating saidpump means.

2. The combination with an engine, a. fuel tank, and means for supplyingfuel from the tank to the engine, of pump means for sucking air from thetop of said. tank to main- Auxiliary for regulating said pump and meansfor admitting air to the discharge side of said pump means to dilute themixture delivered yit. v

4. In comblnation, an engine, a fuel tank,

' a conduit through which fuel is fed from the tank to the engine, anair conduit, connected with the tank, and means connected with the airconduit for maintaining a partial vacuum in the tank, said fuel conduitand air conduit being so arranged that the fuel conduit alwayscommunicates with the bot tom of the tank. and the air conduit with thetop thereof.

5. In combination, an engine, a fuel tank, a conduit through which uelis fed from the tank to the engine, an air conduit connected with thetank, said two conduits terminating within the tank, and conduit meanspivotally mounted on said conduits and connecting them with the top andbottom of the tank.

6. In combination, an engine, a fuel tank,

ing them with the top and bottom of the tank, said conduit means beingweighted so as to always remain vertical.

7. In combination, a fuel tank, a conduit through which fuel iswithdrawn from the tank, a conduit throughwhich air is withdrawn fromthe tank to maintain a partial vacuum therein, and means whereby saidfuel conduit and air conduit are maintained in communicationrespectively with the bottom and top of said fuel tank irrespective ofthe angle which said tank may assume.

8. In combination, an en ine, a fuel tank, a pipe for delivering fuelrom the tank to the engine, an air pump, a suction pipe connecting thesuction side of the air pump to said tank, and a discharge pipeconnecting its delivery side to said en ine, the arrangement being suchthat said uel pipe and suction pipe are always in communication with thebottom and top of said tank respectively, and means for regulating saidair 9. n comblnatlon, an engine, a fuel tank, a pipe for delivering fuelfrom the tank to the engine, an air pump, a suction pipe connecting thesuction side of the air pump to said tank, and a discharge pipeconnecting its delivery sideto said en ine, the arrange ment being suchthat said tuel pipe and suction pipe are always in communication withthe bottom and top of said tank respectively, and means for admittingair directly to said discharge pipe.

In wltness whereof, I have hereunto set my hand this fifth day ofSeptember, 1919.-

ELIHU THOMSON.

